@layer layout {
  /*
   * Page Layout
   * No persistent sidebar - navigation via popup menu
   */
  .page {
    display: flex;
    flex-direction: column;
    block-size: 100dvh;
    overflow-y: auto;
  }

  /*
   * Main content area
   */
  .main {
    flex: 1;
    min-height: 0;
    display: flex;
    flex-direction: column;
    padding: var(--block-space) var(--inline-space-lg);
  }

  .main > * {
    max-inline-size: min(100%, 80rem);
    margin-inline: auto;
    width: 100%;
    flex-shrink: 0;
  }

  /* Narrower content for forms and text-heavy pages */
  .main--narrow > * {
    max-inline-size: var(--content-max-width);
  }

  /* Allow full-width content when needed */
  .main--wide > * {
    max-inline-size: none;
  }

  /*
   * Page sections
   */
  .page-section {
    margin-block-end: var(--block-space-xl);
  }

  .page-section:last-child {
    margin-block-end: 0;
  }

  /*
   * Content containers
   */
  .container {
    max-inline-size: var(--content-max-width);
    margin-inline: auto;
    padding-inline: var(--inline-space-lg);
  }

  .container--narrow {
    max-inline-size: 45ch;
  }

  .container--wide {
    max-inline-size: 80ch;
  }

  /*
   * Page title - centered with optional action button
   * Used for main content area headings (not header)
   */
  .page-title {
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    margin-block-end: var(--block-space);
  }

  .page-title__text {
    font-size: var(--text-3xl);
    font-weight: 900;
    margin: 0;
    text-align: center;
  }

  .page-title__action {
    position: absolute;
    inset-inline-end: 0;
  }

  .page-title__action--start {
    position: absolute;
    inset-inline-start: 0;
  }

  /* On mobile, stack vertically */
  @media (max-width: 640px) {
    .page-title {
      flex-direction: column;
      gap: var(--block-space);
    }

    .page-title__action,
    .page-title__action--start {
      position: static;
    }
  }

  /*
   * Page actions - left-aligned action buttons below title
   */
  .page-actions {
    display: flex;
    gap: var(--inline-space);
    margin-block-end: var(--block-space-lg);
  }

  /*
   * Page header with breadcrumb (for detail pages)
   */
  .page-header {
    margin-block-end: var(--block-space-lg);
  }

  .page-header__breadcrumb {
    margin-block-end: var(--block-space-sm);
  }

  .page-header__back {
    display: inline-flex;
    align-items: center;
    gap: var(--inline-space-sm);
    color: var(--color-ink-muted);
    text-decoration: none;
    font-size: var(--text-sm);
  }

  .page-header__back:hover {
    color: var(--color-link);
  }

  .page-header__title-row {
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
  }

  /* Left-aligned variant */
  .page-header--start .page-header__title-row {
    justify-content: flex-start;
  }

  .page-header__title {
    font-size: var(--text-3xl);
    font-weight: 900;
    margin: 0;
    display: flex;
    align-items: center;
    gap: var(--inline-space);
  }

  .page-header__badge {
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--color-ink-muted);
    background-color: var(--color-canvas-alt);
    padding: var(--block-space-xs) var(--inline-space);
    border-radius: var(--radius-md);
  }


  .page-header__action {
    position: absolute;
    inset-inline-end: 0;
  }

  .page-header__meta {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: var(--block-space-xs) var(--inline-space);
    margin-block-start: var(--block-space-sm);
    font-size: var(--text-sm);
    color: var(--color-ink-muted);
  }

  .page-header__meta-item {
    display: inline-flex;
    align-items: center;
    gap: 0.4ch;
  }

  .page-header__meta-item + .page-header__meta-item::before {
    content: "·";
    margin-inline-end: var(--inline-space);
    color: var(--color-ink-faint);
  }

  .page-header__subtitle {
    text-align: center;
    margin-block-start: var(--block-space-xs);
    font-size: var(--text-sm);
    color: var(--color-ink-muted);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--inline-space-sm);
  }

  @media (max-width: 640px) {
    .page-header__title-row {
      flex-direction: column;
      gap: var(--block-space);
    }

    .page-header__action {
      position: static;
    }
  }

  /*
   * Sticky page header (for pages with sidebar navigation)
   * Positioned below the main app header which is also sticky
   */
  .page-header--sticky {
    position: sticky;
    top: var(--header-height);
    background-color: var(--color-canvas);
    z-index: 9;
    padding-block-end: var(--block-space);
  }
}